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A111520 Sequence is {a(2,n)}, where a(m,n) is defined at sequence A111518. 5
1, 2, 0, -6, -5, 7, -43, -107, 410, -308, -5201, 22426, 1694, -462663, 2209642, 47303, -62434277, 381876639, -384111618, -11477555984, 100411394912, -284526009121, -2378813791310, 34944615773187, -187609218526529, -247374733853554, 14024268845995431 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..26.

EXAMPLE

a(0,n): 1,0,-3,-4,7,...

a(1,n): 1,1,-2,-6,1,...

a(2,n): 1,2,0,-6,-5,...

a(3,n): 1,3,3,-3,-8,...

a(4,n): 1,4,7,4,-4,...

Main diagonal is 1,1,0,-3,-4,..., which is 1 followed by sequence a(0,n).

MAPLE

A111520T := proc(nmax) local a, m, n; a := array(0..nmax, 0..nmax) ; for m from 0 to nmax do a[m, 0] := 1 ; od ; for n from 1 to nmax do a[n, n] := a[0, n-1] ; for m from n+1 to nmax do a[m, n] := a[m-1, n]+a[m, n-1] ; od ; for m from n-1 to 0 by -1 do a[m, n] := a[m+1, n]-a[m+1, n-1] ; od ; od ; RETURN(a) ; end: nmax := 50 ; a := A111520T(nmax) ; r := 2 ; for n from 0 to nmax do printf("%d, ", a[r, n]) ; od; # R. J. Mathar, Sep 26 2006

CROSSREFS

Cf. A111518, A111519, A111521, A111522, A111523.

Sequence in context: A211241 A140247 A271170 * A326040 A145419 A276763

Adjacent sequences:  A111517 A111518 A111519 * A111521 A111522 A111523

KEYWORD

easy,sign

AUTHOR

Leroy Quet, Aug 05 2005

EXTENSIONS

More terms from R. J. Mathar, Sep 26 2006

STATUS

approved

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Last modified October 15 12:31 EDT 2019. Contains 328026 sequences. (Running on oeis4.)